As an instance of known public use, vehicles have come in recent years to be provided with one or a plurality of inflatable airbags, with a view to protecting occupants, and in some cases also pedestrians, during a vehicle accident. Airbags are ordinarily formed of a flexible fabric, but some other flexible sheet material, such as plastic materials, are used in some cases. Airbags come in various forms, for instance so-called driver airbags that protect the driver by inflating from the vicinity of the center of the steering wheel of an automobile, curtain airbags that protect an occupant during a side impact, or during a rollover or overturn accident, by deploying downward on the inward side of an automobile window, and also side airbags that deploy between an occupant and a side panel, so as to protect the occupant during a side impact. The present invention is especially adapted for curtain airbags, but can also be used in airbags of other types without any particular limitations.
The useable packaging space for mounting of airbag devices within vehicles is ordinarily limited, and is often designed to be very small. There are various conceivable reasons for this, for instance aesthetic considerations, and considerations pertaining to the comfort and convenience of the occupants. Accordingly, there are known airbags that are packaged by compression and that take up only a small space in a rolled and/or folded-up state when not deployed.
For instance, structures have been proposed that are provided with a hard plastic cover around an airbag, in order to maintain the packaged state of the compressed airbag and to facilitate mounting of a unit to an automobile, in a simple and reliable manner. However, this significantly increases the cost and weight of an airbag unit, and also the volume of the packaged airbag, and accordingly it is difficult to produce an airbag unit of sufficiently small size. Moreover, a large space is also required during transport, which translates into higher transport costs, due to the fact that the airbag is covered by the hard cover member.
A jump bracket may be used in a curtain airbag device in order to regulate the deployment direction of the airbag. The jump bracket, which is formed of a hard resin or metal, guides the compressed airbag so as to deploy smoothly in a desired direction during inflation. Using a jump bracket entails however an increase in the number of parts, and in a larger airbag package.
A protrusion such as interior door or roof pillar (including a pillar garnish or trim) is typically present in the vicinity of a window in the vehicle side. The curtain airbag device is disposed so as to straddle an intermediate pillar such as a B pillar, and accordingly the pillar garnish may break, or conversely the airbag may be damaged when the airbag hits the pillar garnish violently at the initial stage of airbag deployment.
An object of the present invention, arrived at in the light of the above circumstances, is to provide a curtain airbag device that allows maintaining the shape of a compressed airbag by means of a simple and compact structure.
A further object of the present invention is to provide a curtain airbag device that allows regulating the deployment direction of an airbag through use of a simple structure.
Yet another object of the present invention is to provide a curtain airbag device the structure of which allows precluding situations such as damage to a cabin structure, for instance a pillar garnish, and damage to the airbag, caused by contact between the airbag and the structure during deployment of the airbag.